The evolution of imaging technology is directly linked to new scientific achievements. Scientific imaging has moved many experiments from relying on subjective recording into objectively documentable, repeatable, and quantifiable methods. Demanding and extremely valuable techniques such as single-molecule-based methods would not be possible without appropriate image sensors. The novel quantitative CMOS (qCMOS) technology finally reaches the physical limit: reliable quantification of photon numbers within each pixel, eliminating the influence of technology on the “triangle of frustration” (resolution, sensitivity, speed). This white paper discusses the new image sensor technology that is at the heart of the qCMOS camera. Topics include the semiconductor image sensor, the state of the art approaches to quantitative semiconductor image sensors, The qCMOS image sensor, and the challenges for photon number resolving.
Find detailed information in our White Paper below.

In order to detect weak light with high signal-to-noise, ORCA-Quest has been designed and optimized to every aspect of the sensor from its structure to its electronics. Not only the camera development but also the custom sensor development has been done with latest CMOS technology, an extremely low noise performance of 0.27 electrons has been achieved.

Light is a collection of many photons. Photons are converted into electrons on the sensor, and these electrons are called photoelectrons. “Photon number resolving*” is a method of accurately measuring light by counting photoelectrons. In order to count these photoelectrons, camera noise must be sufficiently smaller than the amount of photoelectron signal. Conventional sCMOS cameras achieve a small readout noise, but still larger than photoelectron signal, making it difficult to count photoelectrons. Using advanced camera technology, the ORCA-Quest counts photoelectrons and delivers an ultra-low readout noise of 0.27 electrons rms (@Ultra quiet scan), stability over temperature and time, individual calibration and real-time correction of each pixel value.

* Photon number resolving is unique and quite different from photon counting (More precisely the method resolves the number of photoelectrons. However, since single photon counting instead of single photoelectron counting has been used for a comparable method in this field, we will use the term “photon number resolving”).

High QE is essential for high efficiency of detecting photons and achieved by back-illuminated structure. In conventional back-illuminated sensors, crosstalks occur between pixels due to no pixel separation, and resolutions are usually inferior to those of front-illuminated sensors. The ORCA-Quest qCMOS's sensor has back-illuminated structure for achieving high quantum efficiency, and trench structure in one-by-one pixel for reducing crosstalk.

Photon counting (PC) level images have typically been acquired using electron multiplication camera such as EM-CCD camera with about 0.3 megapixels. However, ORCA-Quest can acquire not only PC level images but also photon number resolving images with 9.4 megapixels. In addition, it is not fair to compare readout speeds of cameras with different pixel number by frame rate. In such a case the pixel rate (number of pixels × frame rate), which is the number of pixels read out per second, is used. Until now, the fastest camera capable of SPC readout was the EM-CCD camera with about 27 megapixel/s, but the ORCA-Quest enables photon number resolving imaging at about 47 megapixel/s, nearly twice as fast.

Neutral atoms and ions can be regarded as so-called qubits because they can take on a superposition state in which even a single atom has multiple properties. This property is being actively investigated to realize quantum computing and quantum simulation. By observing the fluorescence of trapped ions and neutral atoms, the state of the qubit can be determined, and a low-noise camera is used to read out the fluorescence.

When observing stars from the ground, the image of the star can be blurred due to atmospheric turbulence therefore substantially reducing the ability to capture clear images. However, with short exposures and the right atmospheric conditions, you can sometimes capture clear images. For this reason, lucky imaging is a method of acquiring a large number of images and integrating only the clearest ones while aligning them.

Plants release a very small portion of the light energy they absorb for photosynthesis as light over a period of time. This phenomenon is known as delayed fluorescence. By detecting this faint light, it is possible to observe the effects of chemicals, pathogens, the environment, and other stressors on plants.